282 



Popular Science Monthly 



A slight tap of the paper will cause the 

 filings to take on the lines of the magnet 

 force beneath the paper, as shown in the 

 illustration. It is necessary that the 

 printing paper be handled in a dark room 

 and exposed to a light only after the filings 

 have taken on the lines of force. After the 

 paper is exposed to the light long enough 

 it is develop^ in the usual manner. Blue 

 prints may be made in the same way but 

 the paper must be printed in the sun- 

 light. — Alexander V. Bollerer. - 



A Gas-Lamp Riddle for a Store 

 Window Display 



A GAS-FIXTURE dealer in Brooklyn, 

 N. Y., who was something of a window 

 display expert as well, recently hit upon an 



inn:^ 



The lamp is suspended by wires and is with- 

 out visible connection with the gaspipe line 



ingenious scheme for attracting attention 

 to his window. From an inverted U-shaped 

 gaspipe he suspended by two fine wires a 

 gas-lamp of the inverted incandescent- 

 burner type. The wires were attached to a 

 T-joint from which the lamp hung. The 

 lamp burned brightly and attracted crowds 

 just as he knew it would. Nobody could 

 solve the riddle as to how the gas got into the 

 lamp? The answer was this: Two tiny 

 holes were bored in the upright posts of the 

 U-bend. The holes were aimed exactly at 

 the holes in the end of the gaspipe T-joint. 

 Below the window, the U-joint was con- 

 nected to the gas-main. When the gas was 

 turned on, it shot from the two small holes 

 straight into the ends of the T-joint and the 

 lamp was lighted. 



IS a 



Cleaning Steel Pens with a 

 Glycerine Sponge 



THE illustration shows a European idea 

 that is said to be a decided improve- 

 ment on ordinary pen-wipers. It 

 rubber sponge, wet with 

 glycerine and placed in 

 a glass holder. The 

 sponge does not dry 

 and is always ready. 

 Glycerine takes up 

 liquids readily, and it 

 absorbs the ink from 

 the pen by a mere con- 

 tact or capillary attrac- 

 tion. A thin layer of 

 glycerine adheres to 

 the pen and preserves it, making it take 

 the ink at once when dipped. 



Glycerine-dampened 

 sponge pen-wiper 



Bending Brass and Copper 

 Tubing Easily 



THE following is an easy method of 

 bending brass tubing so that it will 

 not kink or split in the seams: Plug one 

 end of each tube with a piece of soft wood. 

 Place the tubes in an upright position and 

 fill them with hot melted resin. The resin 

 may be heated in a glue pot or a similar 

 utensil. When cool the tubes can be bent 

 to any desired shape. After bending, the 

 resin is removed by holding the tube with 

 the tongs or a rod and applying a blow 

 torch, bunsen burner or other flame. The 

 resin will run out and the tubing will retain 

 its shape. — G. W. Jager. 



A Cigarette Holder Which Expels the 

 Burned End 



THE illustration shows a new cigarette 

 holder fitted with a convenient device 

 for expelling the burned end. This consists 

 of a split ring which fits in the end of the 

 holder as shown. On 

 the outside is a pro- 

 jection joined to the 

 ring so that by push- 

 ing on it the split 

 ring can be slid par- 

 tially out of the 

 holder. The cig- 

 arette is inserted 

 when the ring oc- 

 cupies the inside po- 

 sition. To throw 



The split ring holds 

 the cigarette end 



out the burned end, slide the button for- 

 ward. This opens the split ring and frees 

 the end of the cigarette. 



